基于响应面法的纤维素超低酸水解工艺优化

OPTIMIZATION OF CELLULOSE HYDROLYSIS BY EXTREMELY-LOW ACID BASED ON RESPONSE SURFACE METHOD

采用响应面法对纤维素超低酸水解工艺进行优化研究。以温度、时间、酸浓度和液固比4个因素,根据中心因子复合原则设计31组试验。对试验结果进行二次回归分析,得到响应面模型,相关系数R2=0.8284。方差分析结果表明因素的显著性依次为:温度>液固比>时间>酸浓度。绘制的三维图形均带有明显的凸面,表明最佳工况在本试验设计的水平范围之内。优化结果表明在温度205℃,液固比15.72,酸浓度0.15%,时间33min时获得最大糖浓度为22.35g/L。该条件下,实际试验值为18.75±0.13g/L,与预测值吻合较好。

Response surface method was used to optimize cellulose hydrolysis by extremely-low acid. 31 experiments were carried out according central composite design （CCD） of four factors （temperature, time, acid concentration and liquid-to-solid ratio （L/S）. A response surface model （RSM） was obtained by quadratic regression analysis of experimental data of CCD. The correlation coefficient （R2） was 0. 8284, and the significance is as fol- low： temperature 〉 L/S 〉 time 〉 acid concentration. All the 3D graphics were convex apparently, indicating that the best experimental condition was within the range of this experimental design. The results show that extremely- low-acid hydrolysis of cellulose of the optimum conditions is reaction temperature 205~C, liquid to solid ratio 15.72, 0. 15% acid concentration, reaction time 33rain, the concentration of fermentable sugar is 22.35g/L. Under these conditions, the actual concentration of the fermentable sugars is 18.75 ± 0.13g/L in good agreement well with the predicted values.